/*
 * Copyright (c) 2001-2008 Caucho Technology, Inc.  All rights reserved.
 *
 * The Apache Software License, Version 1.1
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Caucho Technology (http://www.caucho.com/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "Burlap", "Resin", and "Caucho" must not be used to
 *    endorse or promote products derived from this software without prior
 *    written permission. For written permission, please contact
 *    info@caucho.com.
 *
 * 5. Products derived from this software may not be called "Resin"
 *    nor may "Resin" appear in their names without prior written
 *    permission of Caucho Technology.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL CAUCHO TECHNOLOGY OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * @author Scott Ferguson
 */

package com.caucho.hessian.io;

import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 * Serializing an object for known object types.
 */
public class WriteReplaceSerializer extends AbstractSerializer {
	private static final Logger log = Logger
			.getLogger(WriteReplaceSerializer.class.getName());

	private Object _writeReplaceFactory;
	private Method _writeReplace;
	private Serializer _baseSerializer;

	public WriteReplaceSerializer(Class<?> cl, ClassLoader loader,
			Serializer baseSerializer) {
		introspectWriteReplace(cl, loader);

		_baseSerializer = baseSerializer;
	}

	private void introspectWriteReplace(Class<?> cl, ClassLoader loader) {
		try {
			String className = cl.getName() + "HessianSerializer";

			Class<?> serializerClass = Class.forName(className, false, loader);

			Object serializerObject = serializerClass.newInstance();

			Method writeReplace = getWriteReplace(serializerClass, cl);

			if (writeReplace != null) {
				_writeReplaceFactory = serializerObject;
				_writeReplace = writeReplace;
			}
		} catch (ClassNotFoundException e) {
		} catch (Exception e) {
			log.log(Level.FINER, e.toString(), e);
		}

		_writeReplace = getWriteReplace(cl);
		if (_writeReplace != null)
			_writeReplace.setAccessible(true);
	}

	/**
	 * Returns the writeReplace method
	 */
	protected static Method getWriteReplace(Class<?> cl, Class<?> param) {
		for (; cl != null; cl = cl.getSuperclass()) {
			for (Method method : cl.getDeclaredMethods()) {
				if (method.getName().equals("writeReplace")
						&& method.getParameterTypes().length == 1
						&& param.equals(method.getParameterTypes()[0]))
					return method;
			}
		}

		return null;
	}

	/**
	 * Returns the writeReplace method
	 */
	protected static Method getWriteReplace(Class<?> cl) {
		for (; cl != null; cl = cl.getSuperclass()) {
			Method[] methods = cl.getDeclaredMethods();

			for (int i = 0; i < methods.length; i++) {
				Method method = methods[i];

				if (method.getName().equals("writeReplace")
						&& method.getParameterTypes().length == 0)
					return method;
			}
		}

		return null;
	}

	@Override
	public void writeObject(Object obj, AbstractHessianOutput out) throws IOException {
		int ref = out.getRef(obj);

		if (ref >= 0) {
			out.writeRef(ref);

			return;
		}

		try {
			Object repl;

			repl = writeReplace(obj);

			if (obj == repl) {
				if (log.isLoggable(Level.FINE)) {
					log.fine(
							this + ": Hessian writeReplace error.  The writeReplace method ("
									+ _writeReplace
									+ ") must not return the same object: " + obj);
				}

				_baseSerializer.writeObject(obj, out);

				return;
			}

			out.writeObject(repl);

			out.replaceRef(repl, obj);
		} catch (RuntimeException e) {
			throw e;
		} catch (Exception e) {
			throw new RuntimeException(e);
		}
	}

	@Override
	protected Object writeReplace(Object obj) {
		try {
			if (_writeReplaceFactory != null)
				return _writeReplace.invoke(_writeReplaceFactory, obj);
			else
				return _writeReplace.invoke(obj);
		} catch (RuntimeException e) {
			throw e;
		} catch (InvocationTargetException e) {
			throw new RuntimeException(e.getCause());
		} catch (Exception e) {
			throw new RuntimeException(e);
		}
	}
}
